Adafruit 264

DS1307 Real Time Clock breakout board kit This is a great battery-backed real time clock (RTC) that allows your microcontroller project to keep track of time even if it is reprogrammed, or if the power is lost. Perfect for datalogging, clock-building, time stamping, timers and alarms, etc. The DS1307 is the most popular RTC, and works best with 5V-based chips such as the Arduino.

- All parts including PCB, header and battery are included
- Quick to assemble and use
- Plugs into any breadboard, or you can use wires
- We have example code and library for Arduino with a walkthrough on our documentation page
- Two mounting holes
- Will keep time for 5 years or more
- This breakout board is a kit and requires some light soldering which should only take about 15 minutes. Please check the documentation page for a list of parts and assembly instructions

The DS1307 is simple and inexpensive but not a high precision device. It may lose or gain up to 2 seconds a day. For a high-precision, temperature compensated alternative, please check out the ChronoDot.